Buzz
What is aperture?
When you press the shutter button on a digital camera, a hole opens up allowing the camera's sensor to capture the scene you want to photograph, the size of that hole is the aperture. The larger the hole, the more light enters, and the smaller the hole, the less light enters.
Simply put, aperture is the size of the lens opening when taking a photo.
Aperture is measured in 'f-stops', in photography, you often see technical specifications such as f/numbers (f/2.8, f/4, f/5.6, f/8, f/22, ...). Each f-stop will double or halve the lens opening (equivalent to the amount of light received). Remember that each time you increase or decrease a shutter speed, it also changes the corresponding amount of light.
A common misconception many people have is that a larger aperture (allowing more light) corresponds to a smaller f-stop number, and conversely, a smaller aperture (allowing less light) corresponds to a larger f-stop number. So in reality, f/2.8 is much larger aperture than f/22. It might sound counterintuitive at first, but you'll understand this eventually.
Depth of Field and Aperture
There are several things to consider when adjusting aperture, but one of the most important is the depth of field.
Depth of Field (DOF) is the distance of the focus range in a photograph. A large depth of field means most of the image will be sharp whether it's near or far from the focal point. A small depth of field (or shallow) means only a part of the image is sharp, the rest will be blurry.
Aperture significantly affects the depth of field. A large aperture (remember, with smaller numbers) decreases the depth of field, while a small aperture (with larger numbers) increases the depth of field.
There's a bit of confusion about this, but remember, if the aperture has a smaller number, it means a smaller depth of field, and if it's a larger number, it means a larger depth of field.
The best way to understand aperture is to take photos outdoors, experimenting with various subjects at different distances and capturing images with aperture ranging from smallest to largest. You'll quickly notice the changes when adjusting the aperture.
Some shooting styles require a large depth of field (small aperture). For example, in most landscape photos, you'll see photographers often shoot with a small aperture (large number). This ensures that the horizon line in the background remains sharp.
On the other hand, when shooting portraits, it's very useful when you only want to focus on the subject while blurring the background to ensure your main subject stands out. In this case, you need to choose a large aperture (small number) to ensure a shallow depth of field.
Macro photography styles often utilize large apertures to ensure the main subject is in focus to completely capture the viewer's attention while the rest is blurred out of focus.
